I suspect they moved you just out of curtsey rather than actually seeing your status and this requires approval from someone in the premium team. I'd suggest removing the TG number and then adding some other number before re-adding the TG number to see if that makes any difference.

After the phone call are you now able to access the HVC seating online? They are able to add a one off HVC tag to the flight so that premium seating can be selected even when no FF number is in the booking.